Statistics from Altmetric.com
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.
From question on page 1106
Endoscopic ultrasound showed the common bile duct on the left of the image as a linear hypoechoic structure. We noted a tubular non-shadowing structure, 5 mm in diameter, with a hyperechoic wall and a hypoechoic centre inside the common bile duct. The patient underwent endoscopic retrograde cholangiopancreatography (ERCP) (fig 2). The cholangiogram showed an intraductal linear filling defect. An ascaris lumbricoides was trapped with a basket Dormia and withdrawn during duodenoscopy (fig 3).
Ascaris lumbricoides is one of the most common parasitic infestations of the gastrointestinal tract, with over one million people infected worldwide, especially in the Far East, Africa, and subtropical regions. The worms may migrate into the ampulla of Vater and enter the bile ducts, gallbladder, or the pancreatic duct, leading to complications such as biliary colic, gallstone formation, cholecystitis, pyogenic cholangitis, liver abscess, and pancreatitis.1 There is evidence to suggest that sphincterotomy predisposes a patient to biliary ascariasis.2 The diagnosis of pancreatic-biliary ascriasis requires a high degree of suspicion. Ultrasonography is usually the first imaging study and shows a long, well defined, tubular, constant diameter, intraluminal structure with a hypoechoic centre and a more echogenic wall.3 If there are multiple worms, they may completely fill the common bile duct producing the “spaghetti sign”, or they may appear amorphous and manifest as hyperechoic pseudotumours.4 If a diagnosis of pancreatic-biliary ascariasis is made, endoscopic removal of the worm should be attempted.5 Even if this is unsuccessful, conservative treatment with antihelminthic drugs is curative in most cases.
To our knowledge, endoscopic ultrasound imaging of biliary ascaris has not been reported previously. We believe it provides more detailed echogenic information then ultrasonography, allowing more accurate differential diagnosis when it comes to difficult cases.